Two enormous voltage regulator heat sinks, three graphics card slots, and an I/O panel full of connectors are perfect examples of how MSI sees its Z77A-G45 taking back the value crown from a certain similarly-priced competitor. Aesthetics aside, we’ll put those big sinks to use in our heat and overclocking analysis.
Those three long slots are configured as x16-x0-x4 or x8-x8-x4, with the four-lane slot deriving its connectivity from the Z77 PCH. That actually makes this a two-way SLI motherboard, according to both its slot configuration and its silk-screened logo, with the top two slots sharing the CPU’s sixteen PCIe 3.0 lanes. Three-way CrossFireX is available via the third slot, but we wouldn’t hamper any high-end card with so little bandwidth. These slots put the Z77A-G45’s graphics capability on-par with the more-expensive Gigabyte and ECS products in today’s comparison.
The biggest problem with the slots is not configuration, but documentation. MSI refers to the Z77A-G45 as three-way SLI-compatible, but Nvidia doesn’t support a third card through the slower four-lane, second-gen slot. And the documentation foibles don’t end there, as both the manual and specifications page try to convince us that both slots are 16-lane-capable. Four two-lane pathway switches above the top x16 slot let us know otherwise, and we think (or at least hope) that these documentation mistakes were accidental.
MSI saves one of the Z77’s PCIe 2.0 lanes by omitting the PCIe-to-PCI bridge needed by certain competing boards to support legacy slots, and then uses it on a PCIe-based network controller. Only three PCIe 2.0 lanes remain to feed four x1 slots, so MSI decided to connect both of the center x1 slots to the same pathway. These can’t be used simultaneously. Appearing to be a blatant move to artificially bolster the board’s spec sheet, we think MSI should have simply left off the x1 slot immediately below the top x16 interface. The GPU coolers of most high-performance graphics cards cover that slot anyway.
MSI doesn’t include a Port 80 diagnostics display to assist overclocking diagnostics, but does add a row of voltage checking points near the board’s front edge to address an overclocker’s voltage monitoring needs.
The Z77A-G45’s layout is fairly straightforward without any major issues to affect a majority of new builds. Users upgrading older systems may find that their hard drive cage blocks access to the board’s forward-facing SATA and USB 3.0 slots, or even that their front-panel audio cables are too short to reach the bottom-rear corner header. If either of these appear in doubt, we recommend starting your upgrade with a better case.
The Z77A-G45 we received was packaged for a different region, without the SLI bridge we would have expected. A quick check with one of our favorite vendors showed that U.S.-destined boards do get that part, but are still limited to two SATA cables.